The Application Of Silicon-Based Thin Films In The New Devices

Silicon-based thin films have such characteristics as low cost of preparation, mature process equipments, easy integration, no toxicity, broad selectivity of substrate and so on, and has become an important part of industrial production. It plays an irreplaceable role in information, energy and other industries, and is mainly used for integrated circuits, solar battery, photoelectric detector devices. The paper mainly studies two parts:1The preparation technology and principle of Si-NC:SiC,2The deposition and properties of silicon-based resistance random access memory(RRAM).The concept, principles, and study status for Si-based tandem solar cells and resistance random access memory were introduced firstly in introduction. Then in order to improve the density of nanocrystals and control the size of the silicon nanocrystals, intensive study of the process of hot filament chemical vapor deposition technique for depositing Si-NC:SiC films was performed. In the meantime, the effect of gas ratio of SiH4to CH4and working gas pressure on the density and size of nanocrystals was also analyzed carefully. Using X-ray diffractometer (XRD), Raman spectroscopy, Scanning Electron Microscopy (SEM) and Fourier Transform Infra-Red spectroscopy (FTIR) to characterize the of as-deposited films. Secondly, Ag/a-Si/p-Si, Ag/a-Si/Au structure devices have been fabricated by HWCVD, and resistive switching properties were performed by using a Keithley4200Semiconductor Characterization System. The results show that:(1) Both grain size and crystal volume fraction were increased by changing the ratio of SiH4to CH4and working gas pressure. But, the increasing degree of crystal volume fraction is larger than that of grain size in changing working gas pressure, which means the nucleation density is raised. Based on the characteristics of H dilution effect and gas phase reactions, it can be concluded that changing working gas pressure can lead to high density of silicon nanocrystals.(2)The results show that:both Ag/a-Si/p-Si and Ag/a-Si/Au have the bipolar resistive switching behaviors, and also have good repeatability. Based on the I-V curves and the properties of the structures, the switching mechanism for Ag/a-Si/p-Si structure is Ag Conductive Filament and Space Charge Limited Current Mechanism, while the switching mechanism for Ag/a-Si/Au structure is Non-conductive Filament Mechanism.